Very true Vulcan.
The 30-06 can be used for any North American animal, because of the range of different bullets that are available. From the smallest: Prairie Dog, Rabbit, Squirrel...there is a Varmint round that is a sabot round, to the largest: Grizzly, Polar bear, Moose
Current .30-06 factory ammunition varies in bullet weight from 7.1 g to 14.3 g (110 to 220 grains) in solid bullets, and as low as 3.6 g (55 grains) with the use of a sub-caliber bullet in a sabot. Loads are available with reduced velocity and pressure as well as increased velocity and pressure for stronger firearms.
The .30-06 remains one of the most popular sporting cartridges in the world. Many hunting loads have over 2800 ft-lbs of energy at the muzzle and use expanding bullets that can deliver rapid energy transfer to living targets.
Just be sure to sight in after each bullet grain change before you go out hunting, because you will shoot low if you use a heavier bullet grain, or shoot high if you go down in bullet grain.
Hope that this helps.
I use the 150gr when I deer hunt in Oklahoma, but I use 220gr rounds when I hunt in Alaska. Bigger game, bigger bullets.